[CrOS Settings] Add jimmyxgong@chromium.org as OWNER

Change-Id: I160b4cde304ef843070e0dc60fda9c60799cec18
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2365675
Commit-Queue: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: Zentaro Kavanagh <zentaro@chromium.org>
Auto-Submit: Kyle Horimoto <khorimoto@chromium.org>
Reviewed-by: Zentaro Kavanagh <zentaro@chromium.org>
Cr-Commit-Position: refs/heads/master@{#799897}

chrome/browser/resources/settings/chromeos/OWNERS

 jamescook@chromium.org
+jimmyxgong@chromium.org
 khorimoto@chromium.org
 michaelpg@chromium.org
 stevenjb@chromium.org